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751:20220219解碼cda音訊檔格式並讀取音樂光碟(Compact Disc Digital Audio)的音軌<br><table width=800 border=8><tr><td bgcolor=cyan><LI><a href="https://en.wikipedia.org/wiki/Compact_Disc_Digital_Audio#Standard">https://en.wikipedia.org/wiki/Compact_Disc_Digital_Audio#Standard</a>


<LI>libcdio:<a href="https://www.gnu.org/software/libcdio/libcdio.html">https://www.gnu.org/software/libcdio/libcdio.html</a>
<LI>某AudioCD第3軌索引檔<a href="uploads/Track03.cda">Track03.cda</a>
<LI>cda音軌解碼程式：<a href="uploads/cdaParse0.cpp">cdaParse0.cpp</a>
<LI>Eight-to-Fourteen Modulation Conversion Table:
<a href="https://www.physics.udel.edu/~watson/scen103/efm.html">
https://www.physics.udel.edu/~watson/scen103/efm.html</a>

<LI>執行結果如下：
<pre>
0x16-17: numRange=1
0x18-1B: IDByWin=*S
(0x006FFE00)
0x1C-1F: rangeOffset  =0 frames
0x20-23: TotalTrackDuration =19037 total number of frames
0x24: range_position_frames =0 frames
0x25: range_position_seconds =2 seconds
0x26: range_position_minutes =0 minutes
0x27: range_position_null =0x00
0x28: track_duration_frames =62 frames   19307=253*75+62
0x29: track_duration_seconds =13 seconds
0x2A: track_duration_minutes =4 minutes
0x2B: track_duration_null =0x00

--------------------------------

0x16-17: numRange=2
0x18-1B: IDByWin=*S
(0x006FFE00)
0x1C-1F: rangeOffset  =19037 frames
0x20-23: TotalTrackDuration =24713 total number of frames
0x24: range_position_frames =62 frames
0x25: range_position_seconds =15 seconds
0x26: range_position_minutes =4 minutes  
0x27: range_position_null =0x00
0x28: track_duration_frames =38 frames
0x29: track_duration_seconds =29 seconds
0x2A: track_duration_minutes =5 minutes  24713=329*75+38
0x2B: track_duration_null =0x00

--------------------------------
The input file size  is 44 bytes.

0x00-03:ChunkID=RIFF
0x04-07: ChunkSize=36
0x08-0B: Format=CDDA
0x0C-0F: fmt=fmt
0x10-13: ChunkLength =24
0x14-15: 1 for CD Format =1
0x16-17: numRange=3
0x18-1B: IDByWin=*S
(0x006FFE00)
0x1C-1F: rangeOffset  =43750 frames
0x20-23: TotalTrackDuration =30125 total number of frames
0x24: range_position_frames =25 frames
0x25: range_position_seconds =45 seconds
0x26: range_position_minutes =9 minutes
0x27: range_position_null =0x00
0x28: track_duration_frames =50 frames  (=401*75+50=30125)
0x29: track_duration_seconds =41 seconds
0x2A: track_duration_minutes =6 minutes
0x2B: track_duration_null =0x00
</pre>
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參考<a href="http://lfwiki.kmvs.km.edu.tw/lftree/view_article.php?article_id=697">697:20210915解碼wav音訊檔格式</a></table><br> select id,article_id,topic,text from lt_articles_text where article_id =751; ok.
update lt_articles set num_reads=num_reads +1 where id=751; ok.